diff --git a/frontend/app/app/api/chat/route.ts b/frontend/app/app/api/chat/route.ts
index e61b4d1..5b37523 100644
--- a/frontend/app/app/api/chat/route.ts
+++ b/frontend/app/app/api/chat/route.ts
@@ -53,6 +53,7 @@ type ClawStreamItem =
 type StreamState = {
 	textStarted: boolean;
 	textStreamed: boolean;
+	reasoningEnded: boolean;
 	phase: "waiting" | "queued" | "running" | "done";
 	runId?: string;
 	announcedToolCallKeys: Set<string>;
@@ -111,6 +112,7 @@ export async function POST(req: Request) {
 			const streamState: StreamState = {
 				textStarted: false,
 				textStreamed: false,
+				reasoningEnded: false,
 				phase: "waiting",
 				announcedToolCallKeys: new Set<string>(),
 				streamedToolCallIds: new Set<string>(),
@@ -138,12 +140,15 @@ export async function POST(req: Request) {
 				const elapsedMs = payload.elapsed_ms ?? Date.now() - startedAt;
 				const text = formatClawResponse(payload);
 
-				writer.write({
-					type: "reasoning-delta",
-					id: "reasoning-1",
-					delta: `\n思考并执行完成，用时 ${formatDuration(elapsedMs)}。`,
-				});
-				writer.write({ type: "reasoning-end", id: "reasoning-1" });
+				if (!streamState.reasoningEnded) {
+					writer.write({
+						type: "reasoning-delta",
+						id: "reasoning-1",
+						delta: `\n思考并执行完成，用时 ${formatDuration(elapsedMs)}。`,
+					});
+					writer.write({ type: "reasoning-end", id: "reasoning-1" });
+					streamState.reasoningEnded = true;
+				}
 				writeToolTrace(writer, payload.transcript, streamState);
 				if (!streamState.textStreamed) {
 					writer.write({ type: "text-start", id: "text-1" });
@@ -508,6 +513,10 @@ function writeRuntimeEvent(
 	}
 	if (event.type === "content_delta" && event.delta) {
 		if (!streamState?.textStarted) {
+			if (streamState && !streamState.reasoningEnded) {
+				writer.write({ type: "reasoning-end", id: "reasoning-1" });
+				streamState.reasoningEnded = true;
+			}
 			writer.write({ type: "text-start", id: "text-1" });
 			if (streamState) streamState.textStarted = true;
 		}
@@ -531,12 +540,20 @@ function writeRuntimeEvent(
 	}
 	if (event.type === "final_text_start") {
 		if (!streamState?.textStarted) {
+			if (streamState && !streamState.reasoningEnded) {
+				writer.write({ type: "reasoning-end", id: "reasoning-1" });
+				streamState.reasoningEnded = true;
+			}
 			writer.write({ type: "text-start", id: "text-1" });
 			if (streamState) streamState.textStarted = true;
 		}
 	}
 	if (event.type === "final_text_delta" && event.delta) {
 		if (!streamState?.textStarted) {
+			if (streamState && !streamState.reasoningEnded) {
+				writer.write({ type: "reasoning-end", id: "reasoning-1" });
+				streamState.reasoningEnded = true;
+			}
 			writer.write({ type: "text-start", id: "text-1" });
 			if (streamState) streamState.textStarted = true;
 		}